Phase 2a Trial of Elamipretide in FA Patients Likely to Start This Year
A Phase 2a trial assessing Stealth BioTherapeutics‘ lead investigational product elamipretide in people with Friedreich’s ataxia (FA) is expected to initiate by year’s end.
After feedback from the U.S. Food and Drug Administration, the company amended the trial’s design. It now aims to recruit 16 FA patients with vision loss and/or heart disease, who will receive either a high or a low dose of elamipretide.
Previously, the trial planned to enroll 10 patients, and its open-label (no placebo group) design called for a single dose.
Results of this first trial are expected to aid Stealth in designing a pivotal clinical trial to confirm elamipretide’s safety and efficacy in FA patients, which would support a request for regulatory approval.
“We are continuing … to expand our clinical and preclinical development efforts in Friedreich’s ataxia,” Reenie McCarthy, the company’s CEO, said in a press release announcing its quarterly results.
FA is caused by mutations in the gene that carries instructions for the frataxin protein, which is important for the proper functioning of mitochondria, organelles that produce the necessary energy for cellular processes.
Disruptions in mitochondria function may result in a high amount of reactive oxygen species (ROS, also known as free radicals). While healthy and useful in small quantities, ROS in excess can damage and kill cells, and contribute to FA progression.
Elamipretide is designed to aid mitochondria by binding to and protecting cardiolipin, a lipid molecule (a type of fat) located in the inner membrane of mitochondria. Cardiolipin is essential for the normal structure of mitochondria and is particularly susceptible to oxidative stress, or the imbalance between the production and clearance of toxic free radicals.
Prior test results in cells from FA patients demonstrated that elamipretide reduced oxidative stress, increased frataxin levels, and boosted the amount of certain iron-containing compounds that are needed by the mitochondrial proteins to function properly.
A number of mitochondrial properties were also improved with treatment, including their shape and structure, the health of their outer membrane, and several other key measures.
Stealth also is investigating elamipretide in heart disease associated with Duchenne muscular dystrophy and Barth syndrome, as well as in eye diseases associated with mitochondrial problems, such as Leber’s hereditary optic neuropathy and dry age-related macular degeneration.